The links to the cacophonator with input schematic posted earlier are now broken links... ...can anyone who has built one upload the schematic?

Based on the discussion above, the general idea is straight forward, but some details are missing.

The idea: An input signal is brought in through a 4049 hex buffer so its voltage is in the correct range, and also so that it can interact properly with the other oscillators - by coupling through the ground. The output from this 4049 needs to be summed with the oscillator signals, so it likely is added through a 10k resistor to the outputs of oscillators U1A, U1B, U1C, U1D (pins 2,4,6 & 8 ).

This new circuit with input substituted 15k ohm resistors for some of the 10k ohm resistors, for some reason.

This circuit also added four new on-off-on switches and had some doubled capacitor numbers. I.E. 3x C3, 2x C4, 2x C6 and 2x C11. The extra switches likely switch between different timing capacitors for some of the oscillators, and the off position of the switch likely stops some of the oscillators from oscillating.

If anyone can confirm if some of these educated guesses are correct, or even better - repost the schematic, that'd be great!

i suggested to a friend when he built one to add contact points (bolts), one connected to each end of each pot, and it turned out really cool and playable. just wanted to throw that out there. _________________http://www.youtube.com/user/borisandfef

the 4049 is just a buffer to square up an audio input. try building the buffer circuit (check out the datasheet) and then experiment with injecting the signal to different points in the circuit._________________http://www.youtube.com/user/borisandfef

ello
i redraw the caco ii layout in Gimp.
i built it few months ago, and looks ok.
there is 4 jumpers/red,
and i modified some traces...
i didnt find 4049, so the input doesnt tested.
i think its 300dpi.
i hope you can use it.

Nevermind my last post. The cacophonator works fine. I would still really like to build the input circuit if anyone has any more info on it - even the part values for the layout posted above would help.
thanks

Well, I didnt figure out how to make input mod yet, but one day I will...
One thing that turned out to be great, is to power the IC 40106 with the audio out of the atari punk console or a dual lfo or even both. Even a sequencer is fun. It works when you turn the starve pot about halfway.
The bitch- thing is that you can only feed it square or pulse waves. Maybe I find a circuit that amplifies an analog sound the apropriate way, so the cacophonator would accept it. I always get violent when using this 4049 4069 chips, so maybe there is a circuit that uses op amps.

like i said earlier, just run the audio signal (prob through a .1uf cap) through a single buffer circuit (look at the data sheet) on a 4049 or a 4069 and then try inserting the output to different points of the circuit to see what results you get. I'd try the pot first._________________http://www.youtube.com/user/borisandfef

you'll see that the data sheet shows 6 of these ( l>o ) symbols. The input is the flat end and the point is the output. The circle at the point means it is an inverting buffer, so you'll have to run the signal through 2 buffers; like this...
IN --- l>0 -- l>0 --- Out_________________http://www.youtube.com/user/borisandfef

I've just made one of these up for my brother. Not sure if I'm going to send it to him though, it has way too much phase space to explore

I built mine from the schematic posted by screwloose above, but I've patched the 5th oscillator into the output , with the same caps and resistors as oscillator 3 - this gives me a pair of drones (oscillators 1 & 2, and 3 & 5), one "voice" and an unpatched LFO.

I do have one minor problem, though. The signal input isn't working. I get "squared" signal at pin 2 of the 4049, but I suspect C13 is too "phat" - I have no signal on its negative pin. I'm tempted to swap it for a smallish non-electrolytic unless anyone thinks that's a really bad idea.

Oh, and to blu_lu, who smoked r10 - I did exactly the same when I breadboarded, turns out I had VDD and VSS switched on the 40106. Putting the right polarities in place made for a happy circuit, and r10 (well, r9 on screwloose's diagram) stays nice 'n cool.

cooool! I will have to add one of those to my next synth project. Another thing I found a bit weird: Why would the input be sent through one of the oscillators (pin ? Would this add some sort of amplitude modulation to the signal?

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